1. Field of the Invention
The present invention relates to a fin system or connection between a fin (skeg) or daggerboard for a vessel and a vessel, in particular a sailboard or aquafoil, such as a kite board, windsurfing board, surf board, body board, wake board or water ski. The invention also relates to a fin and a fin box (well) suitable for use with the fin system according to the invention.
2. Description of the Prior Art
Although the invention has a broad application, it will be referred hereinafter in short to a fin system and to its application relating to a surf board.
Such fin systems are known in different forms in practice. One form is as follows. A surf board is provided with a mounting box, also known as a fin box or well, sunken in the board at the position where a fin that is to be mounted is to be inserted substantially perpendicularly with respect to the plane of the surf board lying in the water. The fin box is provided locally with first fastening means, such as bore holes, screw holes and suchlike, with which by means of engagement with second fastening means, such as bolts, screws, plugs and suchlike, which a fin has been provided with, the fin can be connected to the fin box and therewith to the surfboard.
A fin serves for compensating the lateral force that in most faring directions is exerted on a surfboard. As a result of this lateral force, were a fin not to be present, the surfboard would not move in the desired direction, with the exception of faring downwind.
The fin will, however, not only provide the desired compensation with respect to the lateral force and directional stability, but also give rise to a certain drag, which must be as small as possible. A fin is therefore designed with regard to optimum hydrodynamic performance within a given set of conditions. When conditions change, for example when higher waves occur, in which a certain fin does not perform optimally, then a need for a different type of fin arises. In practice, a fin is then replaced by a different type of fin, the choice of which is dependent of the desired faring properties.
Also, wear of a different type of erosion of the connection of a fin with the board, or damage to the fin itself, give rise to replacement of the fin. Transportation of a board also forms a reason for removal of a fin.
Since known fins are often connected to surfboards by means of bolts, screws, plugs and suchlike, mounting and removal of the fin are time-consuming. Moreover, hand-held tools are required for mounting and release.